- Zarya Gurvet
Scientists have known for years that measles alters the immune system, but recent evidence suggests that it does not alter the immune system, but rather restores it completely.
Late on November 15, 2019, on the island of Upolu in Samoa – a small part of the Pacific Ocean, somewhere between Hawaii and New Zealand – and government officials rushed to a meeting in the coastal capital to discuss an urgent public health issue. At the end of the evening they immediately declared a state of emergency.
Three months ago, after arriving on a flight from New Zealand, a person developed a rash and exposed red and brown spots, at which time the measles virus broke out. This was soon identified as a “suspicious case” but no further action was taken.
By October 2, seven more measles cases had been reported. Schools – the best environment for the virus to spread among its favorite victims – opened its doors as usual with the simple privilege of banning award ceremonies!
Even then some were ignoring what was happening. But a month later, the outbreak increased to a dangerous rate, and 716 out of a total population of 197,000 were infected with the virus.
But with the imposition of the new emergency law, the country has stepped up efforts to prevent the spread of the disease, schools and businesses have been closed, workers have stopped going to their offices, and officials have advised residents to stay home.
In a scene reminiscent of the red cross placed on the doors when the plague spread in the Middle Ages, red flags appeared outside the homes of vulnerable families across the country, covered in bushes, tied to poles and hung from trees.
Doctors should go door-to-door and force those who need vaccinations. Samoa has become a ghost island as roads are empty and flights are canceled.
Eventually, the infections subsided and the state of emergency was lifted on December 28, 2019. In all, 5,667 people were affected, including eight percent of the population under the age of 15. Of these, 81 died, including 3 children from the same family.
The epidemic was over, but the virus led to “immune forgetfulness”, a mysterious phenomenon that appeared thousands of years ago but was only discovered in 2012. Importantly, if you get measles, your immune system will suddenly forget about all the germs it encountered. Before – every cold, every exposure to every bacterial or viral environment, every vaccine, i.e. the damage is almost permanent.
Current evidence suggests that once the measles infection is over, your body needs to learn anew what is good and what is bad.
“In a way, an infection caused by the measles virus normalizes the immune system as if it had never encountered any microbes in the past,” says Mansour Harever, a professor of immunology at Western University in Canada.
How does measles affect the body? How long does it take? Will this lead to the appearance of other infections?
Measles is an ancient respiratory virus that spreads through aerosols and droplets, and is believed to have appeared about 2,500 years ago when it spread from cattle to humans, using crowded cities around the world.
For thousands of years, measles has affected most children in the world – especially in the first few years of life – almost before their 15th birthday.
In 1967, a year before the vaccine was introduced in the UK, there were 460,407 suspected cases. When European immigrants first came across the Atlantic, the virus was believed to be one of the new imports – along with other diseases such as measles and typhoid – which wiped out 90 percent of the Native American population within a century.
Scientists have known for decades that children with measles are more likely to get sick and die of other causes even after they have recovered. In fact, in a 1995 study, the vaccine reduced the chance of death in the following years from 30 percent to 86 percent.
However, it is not clear why measles causes many illnesses in children.
Then, in 2002, a team of Japanese scientists discovered that the measles virus binding receptor – a type of molecular lock that allows it to enter the body – is not expected in the lungs, but in cells from the respiratory system.
Rick de Swart, an associate professor of virology at Erasmus University Medical Center in the Netherlands, says:
A decade later, a team of international researchers, including Swart, identified measles with a green fluorescent protein and decided to infect the macaque with it and closely monitor where the green virus particles landed.
“We saw that it affects many cells in a systematic way,” Swart says. “Therefore, the virus travels through the bloodstream and infects white blood cells, sending the virus to the lymph nodes, spleen, and all lymphatic tissues.” [غدة في الصدر، وهي جزء من جهاز المناعة]”.
This confirms that measles is an infection that affects the immune system, Swart says.
Measles in the Netherlands in 2013 provided an opportunity to test this theory. The virus first appeared among the Orthodox Protestant community, whose members refused to be vaccinated for religious reasons, eventually infecting 2,600 people. Many years later, scientists examined blood samples taken from patients and confirmed the presence of memory T cells infected with measles.
But that’s not the end of the story, because the medical team found that measles receptors bind to a specific type of immune cell, the memory T cell. Their job is to quietly search for specific pathogens that have been trained to stay in the body for decades after infection. Therefore, measles seriously affects the only cells in the body that can remember what it has encountered before.
But what’s next is confusing scientists to this day with what is known as the “measles paradox”.
“Measles suppresses the immune system while at the same time rejuvenating it,” says Swart. Although measles eliminates immune memories, there is one exception to these losses. Surprisingly, measles is the only virus that your immune system can detect after you get measles.
Measles develops strong immunity to the virus, which leads to lifelong immunity in most people. Although the cause is not yet known, this is the first cause of autoimmune amnesia.
First, measles affects memory cells, and then the immune system learns to recognize the virus somehow. As the immune system begins to produce measles-specific immune cells, they travel throughout the body, preying on infected memory cells, so they end up with cells that can detect measles and kill cells that can identify other viruses. Thus, the virus leads to the destruction of our immune memories.
Eventually, measles replaces all normal immune memory cells with recognizable cells, and nothing else. This means that you are only immune to measles – the immune system will forget about all other germs.
Unfortunately, there is no evidence that restoring the immune system may benefit compromised immune systems, such as those with autoimmune disorders – even so, Swart points out that measles-based therapies do not work. Those who have not yet had measles and have not been vaccinated against measles.
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